et al. investigated research for partial regeneration of the bladder using MSCs in baboon bladder models in which an area of the bladder was surgically ablated. It was found that the MSCs that had populated and engrafted the ablated areas demonstrated the ability for continual expansion and contractile cycles of a functional bladder.
Stem Cell Therapy Research and Challenges
Numerous investigations are being conducted for the regeneration of the entire bladder using bone marrow stem cells and MSCs. Identification and characterization of new sources of stem cells is an essential requirement for the growth of stem cell therapy. Though there are various opportunities for stem cell therapy, an array of challenges is to be faced. A better understanding of bladder cell biology might help devise efficient bladder regeneration therapies. While efficient regeneration or transplantation therapies have been developed, rigorous clinical trials must be performed to measure efficacy and safety. A particular concern is the risk of cancer that is inherent to all stem cell therapies because of the self-renewal capability of these cells. Overcoming these challenges will pave way for a future of bladder therapies.
Suganya Raphael
University of Madras
See Also: Bladder: Development and Regeneration Potential; Bladder: Major Pathologies; Bladder: Stem and Progenitor Cells in Adults; Cancer Stem Cells: Overview; Mesenchymal Stem Cells.
Further Readings
Fierabracci, A., P. Caione, M. Di Giovine, et al. “Identification and Characterization of Adult Stem/Progenitor Cells in the Human Bladder (Bladder Spheroids): Perspectives of Application in Pediatric Surgery.” Pediatric Surgery International, v.23/9 (2007).
Forbes, S. J., P. Vig, R. Poulsom, et al. “Adult Stem Cell Plasticity: New Pathways of Tissue Regeneration Become Visible.” Clinical Science, v.103 (2002).
Nishijima, S., K. Sugaya, M. Miyazato, et al. “Restoration of Bladder Contraction by Bone Marrow Transplantation in Rats With Underactive Bladder.” Biomedical Research, v.28 (2007).
Sharma, Arun K., Matthew I. Bury, Andrew J. Marks, et al. “A Non-Human Primate Model for Urinary Bladder Regeneration Utilizing Autologous Sources of Bone Marrow Derived Mesenchymal Stem Cells.” Stem Cells, v.29/2 (2010).
Woo, L. L., S. T. Tanaka, G. Anumanthan, et al. “Mesenchymal Stem Cell Recruitment and Improved Bladder Function Following Bladder Outlet Obstruction: Preliminary Data.” Journal of Urology, v.185/3 (2011).
Bladder: Current Research on Isolation or Production of Therapeutic Cells
Bladder: Current Research on Isolation or Production of Therapeutic Cells
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Bladder: Current Research on Isolation or Production of Therapeutic Cells
Cellular therapy is a form of medical treatment in which cellular material is injected into a patient. In mainstream medicine, cell therapy is a subject of increasing interest and holds the basis of potential therapeutic benefit. There exists a great potential to use cellular therapy in the treatment of the urinary bladder. Current research on isolation and production of therapeutic cells in the bladder originates from stem cell studies carried out on various sources of these cells. In this article, these origins will be addressed.
Because stem cells maintain the capacity for self-renewal and the ability to differentiate into various cell lineages, they represent an important building block for bladder regenerative medicine strategies. These cells can broadly be classified into embryonic stem cells and nonembryonic cells, also known as adult stem cells. Embryonic stem cells have promising potential; however, researchers are prohibited from studying them, due to ethical and scientific considerations. The use and the study of isolated cells from the bone marrow, umbilical cord, adipose tissue, skin, and amniotic fluid-derived mesenchymal stem cells might be a good alternative for translational activities.
A urinary bladder (black butterfly-like shape) and hyperplastic prostate (BPH) visualized by medical ultrasonography. Stem cells represent an important building block for bladder regeneration. (Wikimedia Commons/Etan J. Tal)
Research on Stem Cells From Urine
Researchers at Wake Forest Baptist Medical Center’s Institute for Regenerative Medicine have identified stem cells in urine that may be differentiated into various cell types. Previously, the team first identified cells that are a small subset of many cells found in urine. The current research furthers the previous studies by confirming the multipotency of the cells. Isolating the cells from urine constitutes relatively minimal processes, according to the researchers. The cells differentiated into three tissue layers, called germ layers: the endoderm, the ectoderm, and the mesoderm. The germ layer is the primary layer of cells that form during embryogenesis. Germ layers eventually give rise to all of an animal’s tissues and organs through organogenesis. This characteristic is a hallmark of true stem cells.
The research team was also able to successfully direct stem cells from urine to become bladder-type cells such as urothelial and smooth muscle, which line the bladder. However, one of the most interesting aspects of the research team’s findings was that the urine-derived cell line may also be used to develop bone, fat, skeletal muscle, nerve, and endothelial cells, which line various blood vessels in the body. The research carried out by the Wake Forest team holds promise for cellular therapy of the bladder and other organs.
The derived stem cells represent virtually an infinite supply of autologous cells to use for medical treatments, not only urology-related such as kidney disease but also erectile dysfunction and urinary incontinence. The cells may potentially also be used to engineer replacement bladders, urine tubes, and other urologic organs. The ability to use a patient’s own stem cells for therapeutic use is highly desirable by clinicians because they do not result in any immune responses or rejections. Stem cells formed using foreign sources may result in immune rejection, which complicates medical treatments. Because tissue-specific cells constitute a very small subpopulation of cells, they can often be difficult to isolate from tissues and organs in the body. Furthermore, unlike induced pluripotent stem cells or embryonic stem cells, the urine-derived stem cells do not form tumors when implanted in the body, which may prove them to be safe for use in patients. The research team suspects that the cells originated from the upper urinary tract, including the kidney. Female study participants who received kidney transplant from male donors were found to have the Y chromosome in their urine-derived stem cells, which suggests that the kidneys may be the source of the cells. Identifying the origins of the urine-derived cells will lead to a clearer understanding of the biological function of multipotent populations of mesenchymal cells within the urinary tract system.
Research on Stem Cells From Bone Marrow
Mesenchymal stem cells can be isolated from virtually any adult tissue. Researchers have been examining ways to use bone marrow-derived mesenchymal stem cells for tissue repair and regeneration of the urinary bladder. MSCs are an adult stem cell isolated from a variety of adult tissue, including bone marrow, adipose, liver, lung, kidney, and skeletal muscle.
A distinct advantage of bone marrow
